Superoxide radical (O2-) is produced by granulocytes for bactericidal purposes, but is also intimately involved in the inflammatory process. This project will investigate the roles of superoxide in inflammation and the pharmacologic activity of the scavenging enzymes superoxide dismutase as an anti-inflammatory agent. Several animal models of induced inflammation will be utilized, including the reverse passive Arthus reaction, carrageenan-induced foot edema, and immune complex induced glomerular nephritis. The pharmacologic properties of native and derivatized superoxide dismutases are being evaluated.